Seat device for a vehicle

Abstract

A seat device includes a seat part that is capable of changing a posture to a use posture that allows sitting on the seat part and to a non-use posture that does not allow sitting on the seat part. A seat support can support the seat part in a state in which the seat part has been changed to the use posture. A guide member has a free groove that slidably guides a sliding part of the seat support and a regulation groove that regulates sliding of the sliding part in a state in which the seat part has been changed to the use posture. The guide member can be fixed on the seat part. A spring biases the seat support so that the sliding part is held in the regulation groove in the state in which the seat part has been changed to the use posture. A lever may cause the sliding part to slide from the regulation groove to the free groove and allow the seat support to swing downward.

What is claimed is: 
     
       1. A seat for a vehicle comprising:
 a seat part that is generally upward-and-downward swingably supported and is capable of changing a posture thereof to a use posture that allows sitting on the seat part and to a non-use posture that does not allow sitting on the seat part, wherein the seat part has a front end and a rear end, and wherein in the non-use posture, the front end is arranged below the rear end; 
 a support part that is generally upward-and-downward swingably supported and that is configured to support the seat part when the seat part is in the use posture; 
 a guide part fixed to a bottom surface of the seat part and comprising:
 a free groove that slidably guides a predetermined portion of the support part; and 
 a regulation groove that regulates sliding of the predetermined portion in a state in which the seat part has been changed to the use posture; 
 
 a biasing member that biases the support part so that the predetermined portion is held in the regulation groove in the state in which the seat part has been changed to the use posture; and 
 a release member configured to cause the predetermined portion to slide from the regulation groove to the free groove whereby the support part swings in first direction against a biasing force of the biasing member. 
 
     
     
       2. The seat device according to  claim 1 , wherein the regulation groove comprises a first groove section and a second groove section. 
     
     
       3. The seat device according to  claim 2 , wherein the first groove section is configured to regulate or guide a first movement of the predetermined portion during upward swinging of the seat part from the use posture. 
     
     
       4. The seat device according to  claim 3 , wherein the second groove section is configured to regulate or guide the predetermined portion after upward swinging of the seat part from the use posture. 
     
     
       5. The seat device according to  claim 3 , wherein the second groove section is configured to regulate or guide the predetermined portion after upward swinging of the seat part from the non-use posture. 
     
     
       6. The seat device according to  claim 3 , wherein the second groove section is configured to regulate or guide the predetermined portion during release of the release member. 
     
     
       7. The seat device according to  claim 3 , wherein the second groove section is configured to regulate or guide the predetermined portion as it moves between the first groove section and the free groove or vice versa. 
     
     
       8. The seat device according to  claim 1 , wherein the biasing member biases the support part so that the predetermined portion is held in the free groove in the state in which the seat part has assumed the non-use posture. 
     
     
       9. The seat device according to  claim 2 , wherein the biasing member biases the support part so that the predetermined portion is held in the free groove in the state in which the seat part has assumed the non-use posture. 
     
     
       10. The seat device according to  claim 8 , wherein the release member is arranged near an outer edge of the seat part and utilizes an operation part that can be accessed by a worker or user. 
     
     
       11. The seat device according to  claim 9 , wherein the release member is arranged near an outer edge of the seat part and utilizes an operation part that can be accessed by a worker or user. 
     
     
       12. The seat device according to  claim 1 , wherein the release member is arranged near an outer edge of the seat part and utilizes an operation part that can be accessed by a worker or user. 
     
     
       13. The seat device according to  claim 2 , wherein the release member is arranged near an outer edge of the seat part and utilizes an operation part that can be accessed by a worker or user. 
     
     
       14. The seat device according to  claim 1 , wherein the seat device is a passenger or auxiliary seat arranged in a vehicle cabin. 
     
     
       15. A vehicle seat comprising:
 a seat part that is generally upward-and-downward swingably supported and is capable of moving between a use posture that allows sitting on the seat part and a non-use posture wherein the seat part is usable for sitting, wherein the seat part has a front end and a rear end, and wherein in the non-use posture, the front end is arranged below the rear end; 
 a support part that is generally upward-and-downward swingably supported and that is configured to assume a position supporting the seat part in the use posture; 
 a guide part fixed to a bottom surface of the seat part and comprising a groove configured to guide movement of a portion of the support part between the use posture and the non-use posture; 
 a biasing member that biases the support part during a swinging movement of the support part from use posture, 
 wherein, in the use posture, the biasing member is oriented along a first direction and the groove is oriented along a second direction that is different from the first direction. 
 
     
     
       16. The seat device according to  claim 15 , wherein the portion of the support part is prevented from engaging with the groove until a user activates a release member. 
     
     
       17. A work vehicle seat comprising:
 a seat part that is swingably mounted and is capable of moving between an up deployed position allowing seating and a non-deployed and folded-down position, wherein the seat part has a front end and a rear end, and wherein in the non-deployed and folded-down position, the front end is arranged below the rear end; 
 a support that is swingably mounted and is capable of moving between a supporting position wherein the seat part is in deployed position and a non-supporting position wherein the seat part is in the non-deployed and folded-down position; 
 a guide fixed to a bottom side of seat part and comprising first and second groove sections configured to guide movement of a portion of the support between the up deployed position and the non-deployed and folded-down position; 
 a biasing member biasing the support toward the supporting position; and 
 a release member accessible to a user, 
 wherein the portion of the support engages with the first groove section at least when the seat part moves upward from the up deployed position, and 
 wherein the portion of the support is prevented from engaging with the second groove section until the user activates the release member. 
 
     
     
       18. The seat device according to  claim 17 , wherein the seat is a passenger or auxiliary seat arranged in a work vehicle cabin. 
     
     
       19. The seat device according to  claim 1 , wherein the support part is structured and arranged to rotate around a different axis than the seat part. 
     
     
       20. The seat device according to  claim 1 , wherein the biasing member is a spring.